Most of the other speeds were within 10%, and a few, spot on. Apart from the fastest speed on each shutter, I'd kinda hoped for reasonably accurate timings - Not wanting to send the mechanisms away for a CLA, is there anything that I could do to improve the speeds ?

Sometimes bad results implicate the test and not the subject. Are you certain that your test method is reliable?

Repeated the tests again this morning, and the results are within 2% or so.

Originally Posted by ic-racer

The Compur is fully adjustable. The manuals are out there

Seems there are quite a few places selling the Rollie manuals. Reluctant to shell out $35+$13 without knowing if the required information is included. Looks like ebay #360153020687 would cover two of the shutters in question.

When you measure high speed leaf shutter opening time, you need to think about the effective opening time. For that, I think you need to integrate the amount of light that pass through and not just looking at the opening and closing time.

When calibrating my shutter using a phototransitor and my sound card, I realized that the highest speed are off quite a bit. About 0.20 stop at 125, 0.5 stop at 250 and about a full stop at 500. The other speeds are within 0.10 of a stop. Since I'm not able for now to get the DC component of the signal, I can't validate my assumption. As soon as I can get my hands on a DAQ card, I will check if integrating the signal make a more sense.